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Calculate the heat required to sublime 10 grams of dry ice (carbon dioxide) at its melting point (-78.5°C) and convert it to a gas at its boiling point (-57°C). The heat of sublimation of carbon dioxide is 25.2 kJ/mol.

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To calculate the heat required to sublime 10 grams of dry ice, we first need to determine the number of moles of carbon dioxide  CO2  present in the sample. The molecular weight of CO2 is 12.01 g/mol  C  + 2 * 16.00 g/mol  O  = 44.01 g/mol.Number of moles = mass / molecular weightNumber of moles = 10 g / 44.01 g/mol = 0.227 molesNow, we can calculate the heat required for sublimation using the heat of sublimation  25.2 kJ/mol .Heat for sublimation = number of moles * heat of sublimationHeat for sublimation = 0.227 moles * 25.2 kJ/mol = 5.72 kJNext, we need to calculate the heat required to raise the temperature of the gaseous CO2 from its melting point  -78.5C  to its boiling point  -57C . To do this, we need the specific heat capacity of gaseous CO2, which is 0.846 J/gC.Temperature change = final temperature - initial temperatureTemperature change = -57C -  -78.5C  = 21.5CHeat required to raise the temperature = mass * specific heat capacity * temperature changeHeat required = 10 g * 0.846 J/gC * 21.5C = 182.13 JSince we want the answer in kJ, we need to convert Joules to kJ:182.13 J *  1 kJ / 1000 J  = 0.182 kJFinally, we can add the heat required for sublimation and the heat required to raise the temperature to find the total heat required:Total heat required = heat for sublimation + heat to raise temperatureTotal heat required = 5.72 kJ + 0.182 kJ = 5.902 kJTherefore, the heat required to sublime 10 grams of dry ice and convert it to a gas at its boiling point is approximately 5.902 kJ.
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